The comments from the 99-year-old investor and sidekick to billionaire Warren Buffett come as turmoil ripples through the country's financial system, which is reckoning with a potential commercial property crash following a handful of bank failures.

"It's not nearly as bad as it was in 2008," the Berkshire Hathaway vice-chair told the Financial Times in an interview. "But trouble happens to banking just like trouble happens everywhere else. In the good times you get into bad habits . . . When bad times come they lose too much."